It shall be, if [such a sin] is committed inadvertently by the congregation, it being hidden from their eyes, the entire congregation shall offer one young bullock for a burnt offering…and one he-goat for a sin-offering. (Num. 15:24)
Rashi comments that the word "sin-offering" [chatat] is written with the letter alef.
The Master of the World can be found even in the sins of a totally wicked person….
If a person has complete knowledge and faith that in every concealment and foreign thought G-d's Presence is hidden, then there is no concealment at all. This is because the knowledge and faith that the Master of the World, the Divine Life-force, is in every movement and thought, both big and small, immediately causes "the workers of iniquity to be dispersed" (Psalms 92:10). The evil falls away and the divine light and life-force becomes revealed. The Master of the World can be found even in the sins of a totally wicked person, in one who is burning to sin. The only exception is the sin of idolatry, as it is written, "…one he-goat for a sin-offering," which lacks the letter alef. [The alef represents the "Alupho shel Olam" - or "the Master of the world"].
A person should think: "How can I make my Creator angry by misusing the very life-force that He gives me, and seeing that He is actually with me? How can I commit this great evil?" One should even partake of permissible desires with a spirit of holiness and humility, and with an awareness of the divine vitality within them. If you do this, you will easily dispel the evil, and become a different person - a holy person who is bound in love to G-d, who experiences true "love of delights" (Songs 7:7). You will easily attain Divine Inspiration, and the spirit of G-d will guide you.
Sometimes, however, [the verse applies]: "Hiding, I will hide My face" (Deut. 31:18). Then, the concealment itself is hidden, and a person does not feel any vitality at all. He knows nothing, and forgets that G-d is with him. This happens because he lost his faith and trust in G-d and turned to false gods. At that moment he is subject to divine retribution. For as long as a person clings to G-d in perfect faith, no evil can befall him at all - only love and affection.
[Excerpted from Leket Imrei Peninim, p.206b, in Sefer Baal Shem Tov on the Torah.]